Thank you for the hint with the library path. That was my fault. Because I forget so quickly, I documented that KnockBang setup in my wiki. http://www.rudiswiki.de/wiki9/AVRTinyISP#KnockBang_serial_protocol

Please take a time to read the details, if I have all necessary documented.

// the loop routine runs over and over again forever:void loop() { digitalWrite(led, HIGH); // turn the LED on (HIGH is the voltage level) delay(1000); // wait for a second digitalWrite(led, LOW); // turn the LED off by making the voltage LOW delay(1000); Serial.println( "Testing..."); // debug output}

I think the buty about Serial Relay is that you have two way communication. This makes the tiny environment look and feel almost like an Arduino.

If you want to utilize this feature you have to use SoftwareSerial, atleast that is my understanding.On the other hand I can see the advantage of using the TinyDebugSerial: You can take a Arduino sketch an compile it for a tiny without midifying the Serial.print() statements.